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You could get the continuously variable output level with a logic gate (buffer or inverter) supplied from a variable voltage.
It's output impedance might change with supply level, but tiny gates (single inverter like 74lvc1g04) can tolerate higher drive than the supply no problem.
This in combination with (analog switch selected) attenuators could give a wide range of continuously variable output levels. Maybe no need to chain the analog switches, then.
Don't think the gate delay is of much relevance here? To drive transmission lines, you want a good match to 50R to make the square edges look clean.
This can be done by always having some minimal attenuation to improve match.
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AFAIU it's only the 100Mhz version that is discontinued.
Still crossing my fingers to actually get mine (hopefully by the end of next week if Jeulin.fr keeps its promises !) !...  :scared:
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How do you implement variable level with diode clipping?
4
You may buffer the two inputs of your diff amplifier with two opamps, each wired as the none-inverting buffer, for example.
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Beginners / Re: Help identifying some (likely older) compontents.
« Last post by Roehrenonkel on Today at 10:54:20 am »
Hi Traceless,
 
1.: My guess is delay-line for TV (Thomson),
     nice resistors, but probably adictive - so send them to me. ;-)))
   Would like to know the manufacturer.
2.: Styroflex-C 27pF
3.: Rohm. Arrays of individual Rs exist as well.

Best regards
6
Test Equipment / Re: Rigol DMM DM858 comparison thread
« Last post by Kleinstein on Today at 10:52:41 am »
The meters has the rather large memory for logging data and the big scree may also be a bonus - especially if if supports using the full screen for really large digits. This could be a thing for educational use (demonstration experiments). The limited AC bandwidth is indeed a bit disappointing.

Compared to a handheld meter one gets main supply (can be a bonus, but not always), the graphics features (no idea how useful) and 4 wire ohm function.
As a somewhat comparable meter I would look at the Sigilent SDM3055, or for the form factor maybe the Keysight EDU34450.
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Dodgy Technology / Re: Ecology vs Disposable Electronic Cigarette
« Last post by Zero999 on Today at 10:51:15 am »
Quote
There have been studies that time and time again proving that the taxes don't cover the increased healthcare costs.
no need to waste money on studies ,smoking in the uk cost the nhs about £3 billion,tax revenue from tobacco £10 billion for  2022-23.
3 Billion? Not even close:
https://ash.org.uk/media-centre/news/press-releases/new-figures-show-smoking-costs-billions-more-than-tobacco-taxes-as-consultation-on-creating-a-smokefree-generation-closes
But honestly, I don't think I wish to discuss this further, because both of us are talking out of or arses about something we don't understand because it's not driven by electrons.
Did you look at the website citing that study? ASH (Action on Smoking and Health) are an anti-tobacco charity, so it's in their interests to cite information which makes smoking look as bad as possible.

It's very difficult to come to an exact figure regarding the costs of something like tobacco. This isn't helped by the fact that people will cherry pick data and bias studies to suite their point of view.

Banning tobacco will also be costly. It will become an illicit drug, which means criminal organisations will fill the void, left by legal manufactures and retailers.

I don't smoke myself, but am biased towards libertarianism and as fewer laws as possible.
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Test Equipment / Re: Program that can log from many multimeters.
« Last post by Messtechniker on Today at 10:46:46 am »
Found a bit of annoyance.
In the window "Scales for chart" and in "Maximum", the entered value there is only visibly retained provided 8 digits after the decimal point is not exceeded.

When entering more than 8 digits after the decimal point "0" is always displayed. But even so, an entered value having 11 digits after the decimal, for example, is honoured in the "Chart" window.

This came to light when measuring small capacitances of around 4 pF. Here "Auto" scaling does not work, so that the maximum chart value needs to be entered manually. 11 digits after the decimal points are needed in my case (UT622E) to display the 1 to 10 pF range, for example.
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Repair / Re: Used Test Equipment Re Cap And Maintenance Advice
« Last post by colorburst on Today at 10:46:38 am »
I find that preventative maintenance adds very little value to used equipment and sometimes is a negative even.

Many hobbyists prefer to do the work themselves. In fact, the late Jim Williams was said to pay more for broken equipment than working!
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Microcontrollers / Re: Minimal GNU Arm Toolchain?
« Last post by DELTA67 on Today at 10:44:15 am »
THANKS  all for your contribution in this thread.
As a conclusion  It's more a waste of time than a waste of HDD space !
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